Fastening devices have long been helpful in the cabinet-making industry by providing a positive latching mechanism that is efficient, simple to operate and economical to produce. The fastening device on a wall cabinet, or a closet, provides integrity to the structure by keeping the door closed and latched.
As business and home life becomes more and more hectic, there are many instances when a simple latching mechanism, one that takes a free hand to unlatch, becomes more of a nuisance than a help. As these problems continued, the push release fastening device gained in popularity, and is now in wide use.
U.S. Pat. No. 2,637,576 to R. K. Nottingham is one example of a push release device. That patent shows a plunger in the form of a flat bar and a latch having a bight portion, used to capture an inserted keeper head. While push release devices of the type shown in the Nottingham patent have been used heretofore in the form of relatively large push release devices, there are a number of inherent problems in such structures which make them inappropriate for constructing relatively small devices as, for instance, a device which may be 11/2 inches long by 3/4 inches wide and about 3/8 inches deep. The problem of constructing such a relatively small device in the form shown in the Nottingham patent arises from the fact that the structure and operation of such devices involves movable sockets which engage fixed pins. In a relatively large device it is possible to provide not only a rigid movable piece in which such sockets are formed, but also to provide sufficient force in the form of multiple springs to carry out the motion of such movable piece and such integral sockets. However, as the size of such a push release device gets smaller and smaller a point is reached where the construction of a movable socket device becomes impractical and its operation becomes less and less reliable. I have discovered that the problems associated with movable socket push release devices can be overcome by forming sockets which are immovable, which are integral with the housing of the device and providing projections which are integral with a movable catch member. These projections are moved into and out of such fixed sockets as the catch member is rotated and one of such projections is provided with a cam surface for engagement with a separately movable element which forces such projection into firm engagement with the uppermost fixed socket. Since such fixed sockets are immovable, the catch member projections are snapped positively and firmly into engagement with the respective sockets. This action is described hereinafter in more detail.